VI Autologous Bone Marrow Transplantation.pdf - Blog Science ...

patients. Not surprisingly the PSCT group had a higher proportion of low grade
patients (37%) compared to the ABMT group (9%) however this proportion was
maintained among patients achieving a CR (33% versus 14%) and patients surviving
disease free to the time of analysis (29% versus 14%). Consequently, the
histological grade of the lymphomas was not a significant factor in differences in
outcomes between the groups.
At 100 days post-transplant, 12 of 20 (60%) PSCT patients were in CR and all
originally had histologically positive marrows but were recipients of culture
negative apheresis harvests. Twenty-six of 45 (58%) évaluable ABMT patients
achieved a CR at 100 days and 14 received culture negative marrow harvests,
whereas 12 received culture positive harvests. Therefore there were no differences
in the proportion of PSCT or ABMT patients achieving a CR at 100 days.
There was no difference in the grade of lymphoma between patients with culture
positive and negative harvests or between the patients achieving a CR and
the entire group of patients.
There were however subsequent differences in outcome of these groups of
patients. For patients achieving a CR at 100 days, the actuarial disease free survival
projected to 5 years of the histologically marrow positive patients receiving
PSCT with culture negative apheresis harvests was 58%, of the ABMT patients
receiving culture negative bone marrow, 50% and the ABMT patients who received
a culture positive marrow, 17%. These results indicate that tumor contamination
of the infused harvest is associated with a significantly poorer outcome.
This further suggests that the most likely cause of progression of disease
in patients who achieve a CR at 100 days is re-infusion of tumor although we
cannot exclude that culture detection of tumor is a surrogate which identifies
more aggressive tumors. A very significant proportion of patients experience
progression despite receiving culture negative harvests therefore tumor which
survives high dose therapy also remains a major problem.
These results also suggest that unless investigators are going to undertake
rigorous screening of marrow harvests for the presence of minimal disease, they
would be more likely to achieve a superior clinical result by employing PSCT
rather than ABMT.
Breast Cancer and Gynecological Epithelial Tumors: This series comprises
29 patients who had breast cancer (23) or cancer of the ovary or cervix (6). They
are part of a larger series of patients of whom those with histologically negative
and culture negative bone marrow underwent, or are candidates for, ABMT.
However, there are too few ABMT recipients to date to make a meaningful comparison
of ABMT versus PSCT for these patients. The 29 patients above all were
scheduled to undergo PSCT because of a marrow abnormality, largely histological
evidence or otherwise culture positivity for tumor or hypocellularity. The
apheresis harvests were also subjected to evaluation by culture for the presence
of suspected malignant epithelial cells. Note that we have not been able to confirm
that these are malignant tumor cells, for example, by growth in immunodeficient
mice, potentially because too few cells (by several logs) are obtained for
evaluation. Of the 29 patients, 6 had suspicious epithelial cells in their apheresis
harvest, one patient died before transplant and three others shortly after transplant.
Only 1 of 5 patients transplanted with a suspicious harvest is currently
alive. Of the 23 patients receiving culture negative harvests, 11 (48%) are alive
SIXTH INTERNATIONAL SYMPOSIUM ON AUTOLOGOUS BONE MARROW TRANSPLANTATION 225